I'm trying to get the noise down on a new GMS 46 2-stroke. I'm currently running a 11-6 Master Airscrew G/F Series and need to lower it by about 1 db for our field. I've already shimmed the head to lower the RPM (now at about 11,500) and put the rubber hose extension on the muffler. I don't want to go to an 11-7 if I can help it due to the higher speed (still learning to land!). The plane doesn't have the clearance to go to a 12" prop without buying new gear or larger tires.

Would a different series or brand of prop give me a lower noise level at the current 11-6 size, or do I just have to get the rpm's down by going to a greater pitch?